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/*
* esodata - data structures and other things, of varying utility
* Copyright 2022, Ben Culkin
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
package bjc.funcdata.theory;
import java.util.Set;
import java.util.function.Function;
import bjc.data.Pair;
import bjc.esodata.PairMap;
// NOTE: haskell uses Category cat: ... where the parameter is the arrow type
public interface Category<Element, Arrow> {
Arrow identity(Element elem);
Arrow compose(Arrow left, Arrow right);
}
// Java objects would form a category as Category<Class<?>, Function<?, ?>>
class FuncCategory implements Category<Class<?>, Function<?, ?>> {
@Override
public Function<?, ?> identity(Class<?> elem) {
return (vl) -> vl;
}
@Override
public Function<?, ?> compose(Function<?, ?> left, Function<?, ?> right) {
// right.compose((Function<? super V, ?>) left);
return null;
}
}
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